Mitsubishi Galant 9G. Manual — part 459

AUTO-CRUISE CONTROL

TSB Revision

ENGINE AND EMISSION CONTROL

17-54

SYMPTOM CHART

M1172002300366

SYMPTOM

INSPECTION
PROCEDURE NO.

REFERENCE
PAGE

Communication with
scan tool is not
possible

Communication with all systems is
impossible

-

Group 13A, MFI
Diagnosis

−

Symptom
Procedures

−

Inspection
Procedure 1

P.13A-967

<2.4L

engine>.
Group 13B, MFI
Diagnosis

−

Symptom
Procedures

−

Inspection
Procedure 1

P.13B-1013

<3.8L

engine>.

Communication with the PCM only is
impossible

-

Group 13A, MFI
Diagnosis

−

Symptom
Procedures

−

Inspection
Procedure 2

P.13A-970

<2.4L

engine>.
Group 13B, MFI
Diagnosis

−

Symptom
Procedures

−

Inspection
Procedure 2

P.13B-1016

<3.8L

engine>.

Auto-cruise control
system is not
cancelled.

When brake pedal is depressed

1

P.17-55

When selector lever is moved to "N" range 2

P.17-55

When "CANCEL" switch is turned ON

3

P.17-55

Auto-cruise control system cannot be set.

4

P.17-56

Hunting (repeated acceleration and deceleration) occurs at the
set vehicle speed.

5

P.17-59

When "CRUISE" (MAIN) switch is turned "ON", "CRUISE"
indicator light inside combination meter does not illuminate.
(However, auto-cruise control system is normal).

6

P.17-61

AUTO-CRUISE CONTROL

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ENGINE AND EMISSION CONTROL

17-55

SYMPTOM PROCEDURES

INSPECTION PROCEDURE 1: When the Brake Pedal is Depressed, Auto-cruise Control System is not
Cancelled.

.

COMMENT

The stoplight switch circuit is suspected.

.

TROUBLESHOOTING HINTS (THE MOST
LIKELY CAUSES FOR THIS CASE:)

• Malfunction of the stoplight switch.

• Damaged harness or connector.

• Malfunction of the PCM.

DIAGNOSIS

Refer to

P.17-33

, Diagnostic Trouble Code Procedures

− DTC

22: Stoplight Switch System.

INSPECTION PROCEDURE 2: When the Selector Lever is Moved to "N" Range, Auto-cruise Control
System is not Cancelled.

.

COMMENT

The transmission range switch circuit is suspected.

.

TROUBLESHOOTING HINTS (THE MOST
LIKELY CAUSES FOR THIS CASE:)

• Malfunction of the transmission range switch.

• Damaged harness or connector.

• Malfunction of the PCM.

DIAGNOSIS

Refer to GROUP 23A, A/T Diagnosis

− Diagnostic Trouble

Code Procedures

− DTC 27: Transmission Range Switch Sys-

tem (Open Circuit)

P.23A-120

, DTC 28: Transmission Range

Switch System (Short Circuit)

P.23A-165

.

INSPECTION PROCEDURE 3: When the Auto-cruise Control "CANCEL" Switch is Set to ON,
Auto-cruise Control System is not Cancelled.

.

COMMENT

The cause is probably an open-circuit in the output in
the circuit inside the "CANCEL" switch.

.

TROUBLESHOOTING HINTS (THE MOST
LIKELY CAUSES FOR THIS CASE:)

• Malfunction of the auto-cruise control switch.

DIAGNOSIS

Replace the auto-cruise control switch. (Refer to

P.17-74

,

Auto-cruise Control).

AUTO-CRUISE CONTROL

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ENGINE AND EMISSION CONTROL

17-56

INSPECTION PROCEDURE 4: Auto-cruise Control System cannot be Set.

.

COMMENT

The fail-safe function is probably canceling
auto-cruise control system. In this case, scan tool
MB991958 can be used to retest each system by
checking the diagnostic trouble codes. The scan tool
can also be used to check if the circuits of each input
switch are normal or not by checking the input switch
codes.

.

TROUBLESHOOTING HINTS (THE MOST
LIKELY CAUSES FOR THIS CASE:)

• Malfunction of the auto-cruise control switch.

• Malfunction of the stoplight switch.

• Malfunction of the transmission range switch.

• Malfunction of the PCM.

DIAGNOSIS

Required Special Tools:

• MB991958: Scan Tool (MUT-III Sub Assembly)

• MB991824: V.C.I.

• MB991827: MUT-III USB Cable

• MB991910: MUT-III Main Harness A

STEP 1. Using scan tool MB991958, read the diagnostic
trouble code.

CAUTION

To prevent damage to scan tool MB991958, always turn the
ignition switch to the "LOCK" (OFF) position before con-
necting or disconnecting scan tool MB991958.
(1) Connect scan tool MB991958 to the data link connector.

(Refer to

P.17-11

).

(2) Turn the ignition switch to the "ON" position.
(3) Check for auto-cruise control system diagnostic trouble

code. (Refer to

P.17-11

).

(4) Turn the ignition switch to the "LOCK" (OFF) position.
(5) Disconnect scan tool MB991958.
Q: Is DTC set?

YES : Diagnose the auto-cruise control system. (Refer to

P.17-14

, Diagnostic Trouble Code Chart). Then go to

Step 6.

NO : Go to Step 2.

AC305412

AB

MB991910

DATA LINK

CONNECTOR

MB991824

MB991827

AUTO-CRUISE CONTROL

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ENGINE AND EMISSION CONTROL

17-57

STEP 2. Using scan tool MB991958, check data list item 04:
Cancel Switch.

CAUTION

To prevent damage to scan tool MB991958, always turn the
ignition switch to the "LOCK" (OFF) position before con-
necting or disconnecting scan tool MB991958.
(1) Connect scan tool MB991958 to the data link connector.

(Refer to

P.17-11

).

(2) Turn the ignition switch to the "ON" position.
(3) Set scan tool MB991958 to data reading mode for

auto-cruise control system. (Refer to

P.17-11

).

• Item 04, Cancel Switch.

• When "CANCEL" switch is at the ON position, the

display on scan tool MB991958 should be "ON".

• When "CANCEL" switch is at the OFF position, the

display on scan tool MB991958 should be "OFF".

(4) Turn the ignition switch to the "LOCK" (OFF) position.
(5) Disconnect scan tool MB991958.
Q: Is the switch operating properly?

YES : Go to Step 3.
NO : Refer to

P.17-55

, Symptom Procedures

− Inspection

Procedure 3. Then go to Step 6.

STEP 3. Using scan tool MB991958, check data list item 05:
Stoplight Switch and data list item 06: Brake switch.

CAUTION

To prevent damage to scan tool MB991958, always turn the
ignition switch to the "LOCK" (OFF) position before con-
necting or disconnecting scan tool MB991958.
(1) Connect scan tool MB991958 to the data link connector.

(Refer to

P.17-11

).

(2) Turn the ignition switch to the "ON" position.
(3) Set scan tool MB991958 to data reading mode for

auto-cruise control system. (Refer to

P.17-11

).

• Item 05, Stoplight Switch.

• When brake pedal is depressed, the display on scan

tool MB991958 should be "ON".

• When brake pedal is released, the display on scan

tool MB991958 should be "OFF".

• Item 06, Brake Switch.

• When brake pedal is depressed, the display on scan

tool MB991958 should be "ON".

• When brake pedal is released, the display on scan

tool MB991958 should be "OFF".

(4) Turn the ignition switch to the "LOCK" (OFF) position.
(5) Disconnect scan tool MB991958.
Q: Is the switch operating properly?

YES : Go to Step 4.
NO : Refer to

P.17-55

, Symptom Procedures

− Inspection

Procedure 1. Then go to Step 6.

AC305412

AB

MB991910

DATA LINK

CONNECTOR

MB991824

MB991827

AC305412

AB

MB991910

DATA LINK

CONNECTOR

MB991824

MB991827